Filter press



Sept. 12, 1933. SEYMOUR 1,926,115

FILTER PRESS Filed Oct. 7. 1932 A? /z j j T 1/ q INVENTOR 4 a huarui f hi ATTORNEY Patented Sept. 12, 1933 7 UNITED STATES PATENT! OFFICE FILTER PRESS Application October '7, 1932. Serial No. 636,712

2 Claims.

This invention relates to filters of the wellknown type in which a series of pads of blotting paper or similar material are clamped between metal plates. In filters of this type some of the filtered liquid may accidentally seep or leak through the edges of the filter pads, and if the liquid is volatile and combustible, any spark in the vicinity of the filter may cause a fire.

In a filter press of the kind in question the flow of the liquid through the filter produces static electricity, and where the liquid is a nonconductor, such as oil, the electricity tends to accumulate on the metal plates unless conducted away by some means. In presses of this kind the plates are usually supported on metal rails, through which the electricity is discharged, but in the operation of tightening the press it sometimes happens that one or more of the plates are lifted from the rails so as not to contact therewith, and in this case sparks may be produced between such plates and the metal supports or any other adjacent conductors, which may cause fires in case the filtered liquid is of an inflammable nature.

The object of the invention is to insure that all of the plates of the filter press shall be at all times grounded, to discharge any electricity which would otherwise collect upon them. This has been accomplished by connecting each plate with a common ground connector, by means of an individual flexible conductor which permits the necessary movements of the plate in making up and tightening the filter, but insures that the electrical connection shall not at any time be broken during the operation of the filter.

In the accompanying drawing Fig. 1 is an end elevation, partly in section, of a portion of a filter press embodying the present invention, and Fig. 2 is a partial side elevation of the same.

The invention is illustrated as embodied in a filter press of well-known form, comprising a series of metal plates 3 with interposed filter pads. By means of a screw 5 the necessary pressure is imparted to one of the endmost plates when the press is in operation.

The filter plates are supported by two metal rails 6, each plate having laterally projecting lugs 7 which rest upon the rails. Any of the filtered liquid which exudes or leaks through the edges of the pads is retained by a drip pan 8. The rails 6 may be connected to earth, as shown 69 diagrammatically in Fig. 1, so as to serve as the common grounding conductors for the plates. Each plate is provided with a connector 9 of. flexible metal wire or cable. The upper end of this connector is attached, by a union nut 12, to a lug 11 which is riveted to one of the ears '7 of the plate. The lower end of the connector is attached, by means of a union nut 14, to a lug 13 attached to one of the rails 6. This arrangement permits the connector to be detached from the plate or the rail when necessary, but normally the connector is left in place at all times. Since the spaces between adjacent plates are small, the connectors of alternate plates are attached to one of the rails 6, and the connectors of the intermediate plates are attached to the other rail.

Although the rails 6, in the illustrated filter press, are used both as supports for the plates and as the common ground conductors, this is not essential, the important feature of the invention being the use of a common ground connector of any kind, to which the several plates are connected by flexible conductors.

The invention claimed is:

1. In a filter press, the combination, with a series of electrically conductive plates separated by non-conducting filtering material, of a common ground conductor, and a series of flexible ground conductors connecting the plates severally with the common ground conductor.

2. In a filter press, the combination of a series of conductive filter plates, two common ground conductors located on opposite sides of the plates, and flexible conductors connecting successive plates alternately to the opposite ground conductors.

EDWARD D. SEYMOUR. 

